BOTANY WITH BASICS OF HYDROBOTANY (AQUATIC PLANTS OF UKRAINE) - B.Ye. Yakubenko - 2011

X. SEED PLANTS

Stonecrop Family (Crassulaceae)

Perennial, less commonly annual plants with thickened, fleshy leaves and stems. Flowers mostly actinomorphic, cyclic, bisexual, rarely unisexual (then plants dioecious). Inflorescences are dichasia or cymes gathered into corymbs, pleiochasia, or panicles, rarely solitary. Perianth double or simple, 3-, 4-, 5-, or 12-merous. Calyx deeply divided. Petals free or connate at the base; equal in number to the calyx lobes. Stamens equal in number to the petals or twice as many, free or connate at the base. Carpels five or numerous, more or less connate. At the base of each carpel, There is a single scale-like nectary. Fruit is a multipollicolous follicle. Ovules numerous, arranged along the ventral suture of the carpels; seeds small.

The family comprises up to 35 genera and 1,500 species, widely distributed primarily in warm, dry regions of South Africa, Asia, and the Mediterranean. The flora of Ukraine includes 24 species representing five genera. Some of these have been introduced into cultivation as ornamentals.

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Fig. 129. Tillaea vaillantii

Tillaea vaillantii Willd. An annual plant, extremely tiny, 2-6 cm tall; a tenagophyte, entomophilous, anemochore (Fig. 129). Stem ascending or prostrate, sparsely leaved. Leaves opposite, linear, 1.5-3 mm long, connate into a sheath at the base.

Flowers solitary, axillary, tiny, 1.5-2 mm long, bisexual, on pedicels 4-6 mm long. Perianth double, 4-merous; pink petals longer than the sepals. Floral formula: *K₄C₄A₄G_(5). Fruits ovoid, with a short beak.

Flowers in May–June. Reproduces by seeds.

Grows on sandy river banks. Extremely rare in the Steppe zone.